Syntheses of (+)-asperlin 1 were achieved via two different synthetic routes. 1,2-Addition of alpha-furyl anion to (2R,3S)-2-'butyldimethylsilyloxy-3-chlorobutanal 6 gave (1S,2R,3S)-1-(2-furyl)-2-'butyldimethylsilyloxy-3-chlorobutanol 7, which was converted to the chiral intermediate, (1S,2R,3R)-1-(2-furyl)-2,3-epoxybutanol 8 (37% overall yield from 6) for the synthesis of (+)-1. The second synthesis of (+)-asperlin 1 from (2R,3S)-6 was achieved in 8% overall yield, based on a combination of the indium-assisted stereoselective addition of 3-bromopropenyl acetate 9 to (2R,3S)-6 and the ring closing metathesis (RCM) using Grubbs catalyst. (C) 2008 Elsevier Ltd. All riehts reserved.
The naturally occurring antibiotics asperlin and related fungal metabolites containing a 5,6-dihydro-2-pyrone moiety have been synthesized stereoselectively. The propargyltitanium reagent derived from 1-trimethylsilyl-3-(tetrahydropyranyloxy)propyne condensed with crotonaldehyde affords the corresponding erythro alcohol as the major product, which is converted to (±)-asperlin and the related three stereoisomers in seven steps.
(+)-Phomalactone, (+)-acetylphomalactone, (+)-asperlin and their isomers were synthesized from 3-triethylsiloxypropyne and (S, E)-1-formyl-2-butenyl benzoate, which was easily prepared from (2R, 3S, E)-1, 2-cyclohexylidenedioxy-4-hexene-3-ol.
Peculiar Sharpless kinetic resolution of 2-furylmethanol and its application to the synthesis of (+)-Asperlin
作者:Zhi-Cai Yang、Wei-Shan Zhou
DOI:10.1016/0040-4039(95)01170-m
日期:1995.7
A peculiar kineticresolution of E-1-(2-furyl)-2-buten-1-ol (1), which produced two oxidation products, pyranone (2) and epoxyalcohol (3), was developed by using the modified Sharplessreagents. A short synthesis of (+)-Asperlin was achieved starting from the opticallyactiveresolution products.
Syntheses of (+)-asperlin 1 were achieved via two different synthetic routes. 1,2-Addition of alpha-furyl anion to (2R,3S)-2-'butyldimethylsilyloxy-3-chlorobutanal 6 gave (1S,2R,3S)-1-(2-furyl)-2-'butyldimethylsilyloxy-3-chlorobutanol 7, which was converted to the chiral intermediate, (1S,2R,3R)-1-(2-furyl)-2,3-epoxybutanol 8 (37% overall yield from 6) for the synthesis of (+)-1. The second synthesis of (+)-asperlin 1 from (2R,3S)-6 was achieved in 8% overall yield, based on a combination of the indium-assisted stereoselective addition of 3-bromopropenyl acetate 9 to (2R,3S)-6 and the ring closing metathesis (RCM) using Grubbs catalyst. (C) 2008 Elsevier Ltd. All riehts reserved.